1. Field of the Invention
The present invention relates to a coupling mechanism of a pipe, further in details, relates to a coupling mechanism which is applicable even when a connected pipe is elongated or contracted to move or pivoted safely without being influenced thereby, and excellent in ensuring a sealing performance of a connected portion and inexpensive and excellent also in an execution performance.
2. Description of the Related Art
A coupling mechanism of this kind is utilized for connecting a connected pipe in various piping systems of mainly supply and drain pipes, intake and exhaust pipes, power/communication cable protecting pipes or the like in a background art.
There is a coupling mechanism of a background art of inserting a connected pipe to a coupling main body by way of a rubber ring for sealing (JP-A-10-19178).
Further, there is also known a coupling mechanism of such a constitution including detachment preventing means for preventing a connected pipe from being detached from a coupling main body (JP-A-7-139674).
Further, there is also present a coupling mechanism an application of which is filed previously by the applicant and which is easy to execute and excellent in an availability in comparison with the above-described background art (JP-A-2004-239289).
Meanwhile, according to JP-A-10-19178, means for preventing detachment of the connected pipe is not present, and therefore, there poses a problem that an accident of drawing the connected pipe from the coupling main body is liable to be brought about.
In contrast thereto, in order to prevent the accident of simply drawing the connected pipe, as in JP-A-7-139674, there is proposed the coupling mechanism including the detachment preventing means of preventing the connected pipe from being drawn, however, according to the coupling mechanism of such a constitution, there poses a problem that a constitution of the detachment preventing means is complicated, an operation of fastening (or fixing) the detachment preventing means is unconceivably troublesome, an enormous time period is required for an execution thereof. Further, although the connected pipe is solidly prevented from being detached by caulking means, in this case, an elongating or contracting movement or a pivoting movement of the connected pipe cannot be dealt with, on the other hand, in a system of connecting the connected pipe by a screwing system, there also poses a problem that when the connected pipe is thin-walled, strength guarantee is deteriorated by a reduction in a wall thickness.
As a coupling mechanism of resolving the above-described problem, there is present the invention of JP-A-2004-239289, the application of which is filed previously by the applicant. Although certainly, resolution of the above-described problem can sufficiently be dealt with by the JP-A-2004-239289, according to the coupling mechanism of JP-A-2004-239289, it is necessary to form an inner side ring groove (notation 10 in FIG. 1 and FIG. 6 of Reference 3) for containing an inner peripheral side edge portion of a stopper member at a position of an outer peripheral wall of the connected pipe inserted to inside of the coupling main body.
Although the inner side ring groove is present for ensuring connection of the coupling main body and the connected pipe by way of the stopper member, the inventor has conceived that the operation for forming the inner side ring groove is not needed by enabling not to form the inner side ring groove at the connected pipe when possible to be able to finish the invention.
The invention provides a coupling mechanism having advantages to be mentioned especially of resoling all of the above-described problems, achieving a firm sealing effect between a coupling main body and a connected pipe despite a simple constitution, capable of preventing an accident of drawing the connected pipe and capable of dealing with elongating or contracting movement or pivoting movement of the connected pipe, facilitating an execution of integrating the connected pipe and the coupling main body, with no need of preparing a special tool for the execution, capable of instantaneously determining an acceptability of a result of the execution operation by only checking the appearance of the finished coupling mechanism, and capable of dispensing with formation of the inner side ring groove of the connected pipe.